使用python请求模块时的LocationValueError

LocationValueError when using python requests module

我一直在使用请求包与Web进行交互，过去没有任何问题。最近当使用我大约一周没用过的脚本时，我在执行例程requests.get()调用时遇到以下错误：

1	LocationValueError: No host specified.

背景研究

经过大量的谷歌搜索python requests LocationValueError，python requests no host error和python urllib3 LocationValueError的各种排列(根据堆栈跟踪错误由urllib3提出请求使用下面)我只能设法找到埋藏在文件：

exception urllib3.exceptions.LocationValueError

Raised when there is something wrong with a given URL input.

我试过的

我的版本的请求包可能有问题，因为这可能是请求包中使用的最基本的调用之一，我做了以下操作：

重新安装的请求
使用pip创建虚拟环境并安装请求
来自源的已安装请求
expicitly安装urllib3
从源代码安装python 3.4然后尝试了(我现在使用python3.5)

在所有实例中，我使用以下代码来查看请求是否仍然抛出LocationValueError：

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import requests
address = 'http://www.google.com/'
requests.get(address)

这在过去一直有效。我检查了另一台计算机(一台ubuntu笔记本电脑)，它在那里工作，让我认为这个问题是我的电脑特有的。

堆栈跟踪问题

这是我在使用virtualenv和python3.4中安装的请求时获得的堆栈跟踪。

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In [5]: import requests

In [6]: requests.get('http://www.google.com/')
---------------------------------------------------------------------------
LocationValueError Traceback (most recent call last)
in ()
----> 1 requests.get('http://www.google.com/')

/home/michael/Documents/my_test_env/lib/python3.4/site-packages/requests/api.py in get(url, params, **kwargs)
67
68 kwargs.setdefault('allow_redirects', True)
---> 69 return request('get', url, params=params, **kwargs)
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71

/home/michael/Documents/my_test_env/lib/python3.4/site-packages/requests/api.py in request(method, url, **kwargs)
48
49 session = sessions.Session()
---> 50 response = session.request(method=method, url=url, **kwargs)
51 # By explicitly closing the session, we avoid leaving sockets open which
52 # can trigger a ResourceWarning in some cases, and look like a memory leak

/home/michael/Documents/my_test_env/lib/python3.4/site-packages/requests/sessions.py in request(self, method, url, params, data, headers, cookies, files, auth, timeout, allow_redirects, proxies, hooks, stream, verify, cert, json)
466 }
467 send_kwargs.update(settings)
--> 468 resp = self.send(prep, **send_kwargs)
469
470 return resp

/home/michael/Documents/my_test_env/lib/python3.4/site-packages/requests/sessions.py in send(self, request, **kwargs)
574
575 # Send the request
--> 576 r = adapter.send(request, **kwargs)
577
578 # Total elapsed time of the request (approximately)

/home/michael/Documents/my_test_env/lib/python3.4/site-packages/requests/adapters.py in send(self, request, stream, timeout, verify, cert, proxies)
335 """
336
--> 337 conn = self.get_connection(request.url, proxies)
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339 self.cert_verify(conn, request.url, verify, cert)

/home/michael/Documents/my_test_env/lib/python3.4/site-packages/requests/adapters.py in get_connection(self, url, proxies)
247 proxy = prepend_scheme_if_needed(proxy, 'http')
248 proxy_manager = self.proxy_manager_for(proxy)
--> 249 conn = proxy_manager.connection_from_url(url)
250 else:
251 # Only scheme should be lower case

/home/michael/Documents/my_test_env/lib/python3.4/site-packages/requests/packages/urllib3/poolmanager.py in connection_from_url(self, url)
137 """
138 u = parse_url(url)
--> 139 return self.connection_from_host(u.host, port=u.port, scheme=u.scheme)
140
141 def urlopen(self, method, url, redirect=True, **kw):

/home/michael/Documents/my_test_env/lib/python3.4/site-packages/requests/packages/urllib3/poolmanager.py in connection_from_host(self, host, port, scheme)
246
247 return super(ProxyManager, self).connection_from_host(
--> 248 self.proxy.host, self.proxy.port, self.proxy.scheme)
249
250 def _set_proxy_headers(self, url, headers=None):

/home/michael/Documents/my_test_env/lib/python3.4/site-packages/requests/packages/urllib3/poolmanager.py in connection_from_host(self, host, port, scheme)
108
109 if not host:
--> 110 raise LocationValueError("No host specified.")
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112 scheme = scheme or 'http'

LocationValueError: No host specified.

如果有人可以帮助解释错误的原因或指出我正确的方向，那将是最受欢迎的。当我使用request.Session对象获取扩展会话的页面时，也会发生此问题。